The “View full taxpayer SSN” permission determines whether a user can view the full SSN or view a masked SSN.
By default the majority of the roles assigned by TaxSlayer on behalf of the IRS DO NOT allow the preparer to view the Full SSN
This can be controlled at the site level with custom Roles. If you choose to to allow the preparer to view the unmasked SSN, you should take measures to ensure the full SSN cannot be viewed by anyone other than the preparer(s).